Re: 3.14-mw regression: rtl8169 WARNING: DMA-API: exceeded 7 overlapping mappings of pfn 55ebe

[Sander Eikelenboom <linux@eikelenboom.it>]

Hmm ok that last message was false .. sorry for that .. it did happen again without r8169.use_dac=1, it just doesn't seem to happen all the time...

Konrad / Wei, do you happen to know of any xen related change that went into 3.14 merge window that relates to dma / xen networking ?

--
Sander

complete stacktrace:

[  342.710738] ------------[ cut here ]------------
[  342.726890] WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:491 add_dma_entry+0x105/0x130()
[  342.743210] DMA-API: exceeded 7 overlapping mappings of pfn 40b00
[  342.759510] Modules linked in:
[  342.775557] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.14.0-rc1-20140206-pcireset-net-btrevert+ #1
[  342.791706] Hardware name: MSI MS-7640/890FXA-GD70 (MS-7640)  , BIOS V1.8B1 09/13/2010
[  342.807627]  0000000000000009 ffff88005f603828 ffffffff81ad29fc ffffffff822134e0
[  342.823430]  ffff88005f603878 ffff88005f603868 ffffffff810bdf62 ffff880000000000
[  342.839081]  0000000000040b00 00000000ffffffef ffffffff822102e0 ffff8800592b9098
[  342.854572] Call Trace:
[  342.869748]  <IRQ>  [<ffffffff81ad29fc>] dump_stack+0x46/0x58
[  342.884915]  [<ffffffff810bdf62>] warn_slowpath_common+0x82/0xb0
[  342.899710]  [<ffffffff810be031>] warn_slowpath_fmt+0x41/0x50
[  342.914395]  [<ffffffff8147853a>] ? active_pfn_read_overlap+0x3a/0x70
[  342.929166]  [<ffffffff814792c5>] add_dma_entry+0x105/0x130
[  342.943733]  [<ffffffff814796c6>] debug_dma_map_page+0x126/0x150
[  342.957988]  [<ffffffff8171c8b6>] rtl8169_start_xmit+0x216/0xa20
[  342.972306]  [<ffffffff8195f08f>] ? dev_queue_xmit_nit+0x1ef/0x260
[  342.986523]  [<ffffffff8195eea0>] ? dev_loopback_xmit+0x1e0/0x1e0
[  343.000689]  [<ffffffff819631e6>] dev_hard_start_xmit+0x2e6/0x4a0
[  343.014466]  [<ffffffff81980f3e>] sch_direct_xmit+0xfe/0x280
[  343.028052]  [<ffffffff819635dc>] __dev_queue_xmit+0x23c/0x630
[  343.041338]  [<ffffffff819633a0>] ? dev_hard_start_xmit+0x4a0/0x4a0
[  343.054483]  [<ffffffff81a0a334>] ? ip_output+0x54/0xf0
[  343.067659]  [<ffffffff819639eb>] dev_queue_xmit+0xb/0x10
[  343.080804]  [<ffffffff81a0890b>] ip_finish_output+0x2cb/0x670
[  343.093746]  [<ffffffff81a0a334>] ? ip_output+0x54/0xf0
[  343.106391]  [<ffffffff81a0a334>] ip_output+0x54/0xf0
[  343.118683]  [<ffffffff81a05791>] ip_forward_finish+0x71/0x1a0
[  343.130901]  [<ffffffff81a05a63>] ip_forward+0x1a3/0x440
[  343.142829]  [<ffffffff810ffebb>] ? lock_is_held+0x8b/0xb0
[  343.154346]  [<ffffffff81a035c0>] ip_rcv_finish+0x150/0x660
[  343.165748]  [<ffffffff81a0406b>] ip_rcv+0x22b/0x370
[  343.176838]  [<ffffffff81a60972>] ? packet_rcv_spkt+0x42/0x190
[  343.187659]  [<ffffffff819609d2>] __netif_receive_skb_core+0x6d2/0x8a0
[  343.198209]  [<ffffffff81960414>] ? __netif_receive_skb_core+0x114/0x8a0
[  343.208819]  [<ffffffff81009010>] ? xen_clocksource_read+0x20/0x30
[  343.219471]  [<ffffffff81116e49>] ? getnstimeofday+0x9/0x30
[  343.229862]  [<ffffffff81960bbc>] __netif_receive_skb+0x1c/0x70
[  343.239953]  [<ffffffff81960c2e>] netif_receive_skb_internal+0x1e/0xf0
[  343.249908]  [<ffffffff81962110>] napi_gro_receive+0x70/0xa0
[  343.259509]  [<ffffffff817198a3>] rtl8169_poll+0x2d3/0x680
[  343.268982]  [<ffffffff81adcd2b>] ? _raw_spin_unlock_irq+0x2b/0x50
[  343.278091]  [<ffffffff819610d1>] net_rx_action+0x161/0x260
[  343.287056]  [<ffffffff810c28ec>] __do_softirq+0x12c/0x280
[  343.295756]  [<ffffffff810c2da2>] irq_exit+0xa2/0xd0
[  343.304235]  [<ffffffff814ffd5f>] xen_evtchn_do_upcall+0x2f/0x40
[  343.312387]  [<ffffffff81adf15e>] xen_do_hypervisor_callback+0x1e/0x30
[  343.320389]  <EOI>  [<ffffffff810013aa>] ? xen_hypercall_sched_op+0xa/0x20
[  343.328171]  [<ffffffff810013aa>] ? xen_hypercall_sched_op+0xa/0x20
[  343.335738]  [<ffffffff81008c70>] ? xen_safe_halt+0x10/0x20
[  343.343142]  [<ffffffff81018748>] ? default_idle+0x18/0x20
[  343.350202]  [<ffffffff81018f5e>] ? arch_cpu_idle+0x2e/0x40
[  343.356994]  [<ffffffff8110b551>] ? cpu_startup_entry+0x91/0x1e0
[  343.363658]  [<ffffffff81ac7d87>] ? rest_init+0xb7/0xc0
[  343.369924]  [<ffffffff81ac7cd0>] ? csum_partial_copy_generic+0x170/0x170
[  343.376057]  [<ffffffff8230ff1c>] ? start_kernel+0x409/0x416
[  343.381972]  [<ffffffff8230f912>] ? repair_env_string+0x5e/0x5e
[  343.387573]  [<ffffffff8230f5f8>] ? x86_64_start_reservations+0x2a/0x2c
[  343.393152]  [<ffffffff82312e28>] ? xen_start_kernel+0x586/0x588
[  343.398628] ---[ end trace 8379b598fb7ef5ee ]---





Thursday, February 6, 2014, 12:36:31 PM, you wrote:

> Hi Dan / Francois,

> Didn't have time to test it before, but the patch doesn't seem to help.
> I'm still getting the "DMA-API: exceeded 7 overlapping mappings of pfn 55ebe",
> but i see now i forgot to mention i use r8169.use_dac=1 ...

> Not using it seems to prevent the warning, but before 3.14 i have never seen this (with r8169.use_dac=1)

> --
> Sander

> Wednesday, January 29, 2014, 4:06:24 AM, you wrote:

>> On Sun, Jan 26, 2014 at 4:03 PM, Francois Romieu <romieu@fr.zoreil.com> wrote:
>>> Sander Eikelenboom <linux@eikelenboom.it> :
>>> [...]
>>>> I have got a regression with a 3.14-mw kernel (last commit is 4ba9920e5e9c0e16b5ed24292d45322907bb9035):
>>>> It looks like it's related to the rtl8169 ...
>>>>
>>>> --
>>>> Sander
>>>>
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.105537] ------------[ cut here ]------------
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.116779] WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:491 add_dma_entry+0x103/0x130()
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.128148] DMA-API: exceeded 7 overlapping mappings of pfn 55ebe
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.139397] Modules linked in:
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.150535] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.13.0-20140125-mw-pcireset+ #1
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.161784] Hardware name: MSI MS-7640/890FXA-GD70 (MS-7640)  , BIOS V1.8B1 09/13/2010
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.172965]  0000000000000009 ffff88005f603838 ffffffff81acbcfa ffffffff822134e0
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.184156]  ffff88005f603888 ffff88005f603878 ffffffff810bdf62 ffff880000000000
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.195186]  0000000000055ebe 00000000ffffffef 0000000000000200 ffff8800592ea098
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.206227] Call Trace:
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.217027]  <IRQ>  [<ffffffff81acbcfa>] dump_stack+0x46/0x58
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.227907]  [<ffffffff810bdf62>] warn_slowpath_common+0x82/0xb0
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.238678]  [<ffffffff810be031>] warn_slowpath_fmt+0x41/0x50
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.249336]  [<ffffffff81471c5a>] ? active_pfn_read_overlap+0x3a/0x70
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.259904]  [<ffffffff814729e3>] add_dma_entry+0x103/0x130
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.270416]  [<ffffffff81472de6>] debug_dma_map_page+0x126/0x150
>>>> Jan 26 11:36:26 serveerstertje kernel: [   89.280840]  [<ffffffff81714686>] rtl8169_start_xmit+0x216/0xa20
>>> [r8169 and xen stuff]
>>>
>>> Dan, I miss the part of the debug code that tells where the mappings were
>>> previously set.

>> In this case it was a facepalm mistake on my part.  The mappings were
>> not being properly accounted in the last revision of the patch I sent.
>>  I copied you on the fix [1].

>> --
>> Dan

>> [1]: http://marc.info/?l=linux-netdev&m=139096447627032&w=2




-- 
Best regards,
 Sander                            mailto:linux@eikelenboom.it